Need advice on feeding

[jezzeaepi]

Hello Lee,

I have read your post on fish nutrition, and saw your presentation when you came up to Seattle for PSAS a little while back and have since been trying to feed my fish better. Right now I have a rabbitfish that I can never seem to satiate. He always hangs out in his feeding corner, and when I come over to the tank he comes right up to surface and waits for food. He even sort of "begs" by rapidly opening and closing his mouth as if hes anticipating food. I feel I could feed im an unlimited amount and hell always be just as eager to accept another piece of food in 10 minutes. From what I have read and heard, this seems to indicate that he is not getting the proper nutrition despite the fact that hes got good coloration and is not skinny by any means.

The fish:
Coral Rabbitfish
About 6-7inches in length
My food:
I try to have 2 to 3 different kinda of dried algae around. I use Julian sprungs and ocean nutritions products.
For frozen food I feed "Rods reef frozen food" and occasioanly some brine shimp.

My feeding regiments is as follows:
5 to 7 times a day Ill give a 1.5inch x 1.5inch square of algae to my fish, sometimes a little larger.
once every day, sometimes every other day, Ill break off a chunk of rods reef food and feed that and occasionaly include some brine shrimp.


How would you augment my feeding regiment? Is this behavior normal for a rabbitfish?

Thank you,
Jesse

 

[Snowboarda42]

Try soaking the algae sheets in a bit of selcon first

Lee also recommends blanched broccoli flowers, so you might give that a try as well

 

[greenmonkey51]

If he looks nice and healthy why worry. I rarely feed more than once a day and I never use any vitamins. Yet all my fish look good and are presumably healthy. This goes against a lot of stuff I've read.

 

[jezzeaepi]

Any comment Lee?

 

[leebca]

Thanks for your post, Jesse. It is rare that someone has the courage to ask such a question. Most would just ignore the behavior pattern and the fish will continue to behave as such. The 'why change anything if the fish looks good' is a common response to such fish behavior. Your fish though, is trying to communicate a problem.

It may seem obvious, maybe not. But the simple fact is -- that fish isn't getting enough to eat. Have any idea what quantity that size fish consumes in the wild? A LOT!! A school of them will strip a reef of its algae in a few hours. An extremely important member of the ecosystem. But, that's another story.

That 1.5 x 1.5 piece of algae twice a day would be okay for a 1" Tang or smaller. That size of Rabbitfish is expecting about a 6 x 6 piece of algae, twice or three times a day. Get the idea? 1.5 x 1.5 5 times a day is: 11 sq inches. 6 x 6 twice a day is: 72 square inches. Does this put what I'm trying to get across into perspective?

Put in a sheet and see how long it takes for it to be consumed. If it takes less than 1/2 hour to be eaten, then what you put in was not enough. Put in enough so that in about an hour later there is still a little bit around to be eaten. THAT is the right amount.

Herbivores have to eat a very large quantity of plant food to obtain the nutrients that an omnivore would find very easy to fulfill. This is one reason why the herbivores have a (negative) reputation for being tank polluters -- they produce large quantities of fecal matter. Simply put, they make so much because they eat so much.

So, the algae is just the beginning. Better find a 'bulk source' of this.

Next, the fish will require about 30% of whole marine animal products. From your description, this is almost totally missing. Introduce marine mysis, marine plankton, and krill to begin with. That should be about twice or three times a day. The quantity that fish should be expected to consume is about 1 teaspoon full at each of 2 or 3 feedings in between the algae feedings.

As fish grow, hobbyists forget that they will consume a disproportionate quantity of foods. What was fine two years ago is about 1/3 what the fish needs today! It seems based upon your description the fish is getting less than half of its needed quantity and kinds of food.

Your fish is likely saying, 'Feed me' not because of the wrong nutrition, but not enough food. Rabbitfish are known to grow fast and thus, they belong in very long, large display tanks. But they grow as expected when they are being fed properly.

Part of the problem with the current situation is that, even though you (hopefully) will be providing more food, the fish is in the habit of appearing to want more. This behavior may not subside for a few weeks even after the fish is getting its proper fill of food. Behaviors are hard to change, even when no longer warranted.

 

[jezzeaepi]

What kind of algae do you feed? It seems to me that such a large influx of dried algae would certainly cause nitrate and phosphate problems?

 

[leebca]

All marine fish foods contain phosphorous, and the precursors (e.g. nitrogen containing products) to produce nitrates and phosphates. In a FOWLR system this is of minor importance.

In a reef system, then any such large fish, producing a lot of wastes, would not be a good idea in general. However, the usual means of removing nitrates and phosphates would be needed: export by chemical, water changes, refugium, etc. are the control choices.

People think that if they run a refugium with macro algae that they shouldn't put that 'crop' into the display as food because they are putting back into the water the nutrients the macro algae removed. Of course they are put back in -- all foods put these nutrients into the system. That is the fundamental principles of the nitrogen cycle. As I mentioned above, all foods contain those components and withholding the food from fishes to control nitrates and phosphates is not a control choice.

My systems are all FOWLR and although I check nitrates, they are not that important to my marine life.

I feed the algae you have mentioned, uncooked/raw marine algae made into nori type sheets, and my own formula which contains kelp and spirulina.

 

[jezzeaepi]

I have stepped up the feeding and have seen some noticeable improvements. He seems to heal faster when he scrapes himself, and he has a much more vibrant yellow's and blues. Thanks for the tip.

Peace,
Jesse

 

[krisfal]

That 1.5 x 1.5 piece of algae twice a day would be okay for a 1" Tang or smaller. That size of Rabbitfish is expecting about a 6 x 6 piece of algae, twice or three times a day. Get the idea? 1.5 x 1.5 5 times a day is: 11 sq inches. 6 x 6 twice a day is: 72 square inches. Does this put what I'm trying to get across into perspective?

Put in a sheet and see how long it takes for it to be consumed. If it takes less than 1/2 hour to be eaten, then what you put in was not enough. Put in enough so that in about an hour later there is still a little bit around to be eaten. THAT is the right amount.

Wow! Well I am not feeding my tangs nearly enough algae then. They consume it in less then 5 minutes. I feed algae three times a day (I also feed various homemade frozen mixtures of chopped whole seafoods (clam, shrimp etc.), broccoli flowerettes, chopped dried algea, zoecon and selecon, twice a day) . Should the algae sheet last an hour for each of the three feedings? Or are you saying to see how much it takes to last an hour and then split that amount up for the individual feedings.

 

[leebca]

Hi Kris.

At each feeding a very small amount of the macro algae feed should be there for an hour. If the fish consumes the feeding in a few minutes, start by doubling the initial quantity. Keep increasing the quantify until, about an hour after you put it in, there is still a very little bit of it on the clip or floating around. This is then the quantity to offer for that particular feeding. Repeat the exercise for the next scheduled feeding to determine the correct amount for that feeding at that time of day, etc.

In the case of herbivores, they need an increase of algae and decrease the fish flesh as the fish grows. Young herbivores eat pods and the like when the opportunity presents itself, but their digestive system is really that of a herbivore. When they get larger and then cover a much larger area to forage, their algae intake goes up considerably. They will release a lot of waste into the system. If your fish isn't a heavy water polluter, then it isn't getting enough algae.

To the herbivores, macro algae is truly their 'browse.' Like cows, they want to slowly eat algae continuously or whenever they want it, over a long period of time. By limiting the algae offered, the fish is forced to eat hearty and then have nothing in between. The regime of frequent feedings does help offset this roller coaster habit of feast and famine, and that is good.

When it comes to offering macro algae to herbivores, they will regulate their intake fairly well. That is to say, we let them decide how much is enough. However, going through the feast-famine regime, they may overeat when offered more. So 'ramping up' the quantity works to slowly introduce them to the new quantity being offered. After a while, reducing the amount of macro algae would also be a likely scenario as the fishes 'even out' their intake.

When you see too much macro algae around after an hour, then decrease that feeding quantity. Also take note: At the end of an hour, if you guessed wrong or the fish seems uninterested, remove any large quantity of uneaten macro algae. Don't let the macro algae linger around overnight.

 

[leebca]

Jesse,

Good news. You seem to pay very close attention to your fish. Keep it up!

You are more than welcome.

 

[krisfal]

Thanks Lee for the detailed response I will begin ramping up the algae amount and see how it goes.

Thanks Jesse for asking this question so that we can all learn from it!

 

[krisfal]

I have been meaning to get back to this thread and post my results.

After reading this thread I began increasing the amount of algae I was feeding my tangs. Over about 3 weeks I slowly increased the amount until I was feeding 3 times what I was originally feeding. At first the tangs continued to gobble it all down within minutes but then slowly they began to be less frantic at feeding time and eventually I was able to cut back a little as they began to leave some algae for over an hour. I ended up at about 2.5 times what my original amount was. I have also notice a lot less aggression towards each other and the tangs have began to school together again like they use to. It seems with plenty of food that they do not feel the need to be so aggressive (Although my sailfin still likes to challenge my hand in the tank!). I feel bad that I was underfeeding before.

One other observation, my Naso tang is noticeably growing. I bought this fish at a larger size than the other tangs (sailfin, yellow, hippo) and thought that maybe since it was likely more mature was the reason it did not seem to grow as rapidly as the other tangs. In the last few months, with the increased feeding, I can see that he has grown. Although my previous feeding regime seemed to keep the tangs well fleshed out with plenty of reserve it was not enough for the Naso to be growing as well as it could.

Thanks again Lee for your advice and thanks Jesse for asking this question so I and my tangs could benefit from it.

 

[jezzeaepi]

Thats awesome krisfal! My rabbitfish has calmed down considerably since I started feeding him more often. Ive also noticed that he likes mysis and rods reef food a lot more then I though. I can tell when hes hungry for frozen foods because he starts swiming along the sand attempting to stir up food bits that have fallen out of the water column. Ive been feeding frozen twice a day, but know that he really wants it 3 times a day... But I dont remeber to most of the time =\ If only there were some sort of timer based frozen food feeder.

Lee-
I think deciding "how much" is defintly one of the most difficult things to do in this hobby. Algae seems to be pretty easy to figure out how much is needed, but meat based foods seem a lot more difficult. IMO, most hobbyist really have no point of refrence to start from for feeding and consequntly just sort of throw some food in and hope its enough. If the fish starves, they feed more. If the tank shoots up in nitrates/phosphates, they feed less. The area in between is a huge range and to be honest Im just "throwing darts" to decide where in the range to feed. Is there any way you can expand on this in your feeding article? I realize there is no easy formula to use because all fish are different, and as they grow they require more food, but at a decreasing rate. If though, you could say that juvenile rabbitfish eats "approximatley 1 "cubed" sized feeding 3 times a day while an adult needs 3 cubes 3 times a day", or that a group of 3-5 chromis would eat "approximately 1.5 cubes twice a day", then it would give people a much better idea of a starting point. With frozen food I find that often my fish "cherry pick" the best food bits early, then start eatting the smaller pieces a little later so its hard for me to tell when they are done. There is also a lot of food that gets circulated around the tank because I dont like shutting my return off during feeding for several reasons(I put the tunze on standby).

Peace,
Jesse

 

[krisfal]

Jesse, I agree that figuring out the right amount to feed is dificult. When I first started in this hobby a lot of what I read on RF regarding feeding seemed to solely focus on nitrate control so the emphasis was on under feeding, some people even indicate they only feed every other day

I would rather make sure my fish are getting enough food but at the same time do not want to pollute the tank. I have moved to several smaller meals after reading the nutrition information Lee provided, but like you am not sure I am giving enough meaty foods (after all I did not realize I was under feeding algae until this post) as it is all consumed within minutes. I try to disperse the feeding of each meal of frozen over about a half an hour (except in the morning as I just do not have enough time to add a little bit at a time). I look forward to what Lee will respond on the amount of meaty food to feed.

 

[jezzeaepi]

any comment lee?

 

[leebca]

The correct quantity to feed is always a challenge. When I was developing the choice of foods for a nutritional diet, it was (and still is) a major factor in fish husbandry.

The first problem in working with hobbyists is the quantity. How is that measured? You see, foods come in all sorts of water content ratios. "One cube" could be another product's "2 cubes" after water is removed.

The next problem is food content. Using the cube concept, that 1 cube can contain the protein that another product contains in 3 cubes.

The above is an attempt to point out that there is no standard -- no common ground from which we can form a meaningful foundation to determine how much to feed.

Assuming the feed is nutritionally sound or that the diet over all is nutritionally sound then some recommend a time factor. If you read some marine fish feeding containers you'll find directions such as, 'Feed no more than what fish will consume in X minutes.' In many cases, the "X" is a 3. This doesn't work well with all fishes. How does the food manufacturer know how much my fish eat in X minutes? I may have Butterflyfishes that are shy and eat slowly. I may have Damselfishes that eat fast.

Fish in the wild eat throughout the day. A few years ago studies were done to try and figure out how much marine fish are eating. Studies were done based upon the size of the fish, so a kind of ratio was developed between the amount in mass consumed and the body mass of the fish. An astonishing (to me at least) result was that during a 24 hour period, Damselfishes were each eating on the average of 30% of their body mass (in an area where food was readily available).

Unfortunately, the above can't be applied to the wide variety of captive marine fishes. Studies are rarely done on ornamental fishes and the bulky Sea Bass is not a particularly good standard to apply to our laterally compressed fishes. That is to say, we don't have such data for all the ornamental marine fishes.

What can the hobbyist accomplish is close and careful observation, much like a mother or father learns from their very young child. This is hard, I know, but once into the 'grove' of it, the optimal quantity at each feeding, gets to be fairly clear.

If you think it worthwhile, then I would add the following to the post:
Quantity to Feed
Ideally, each fish gets the proper quantity of a custom food formula based upon the fish's body mass, types of food it consumes, and data from field tests. This isn't practical for the marine hobbyist. Feeding for a specific length of time is not the best approach either -- some fishes each slowly and pick, others 'inhale' their food.

What the hobbyist learns from observation is that their fish will eat enthusiastically at the outset of a feeding time. Many marine fishes will eat like there is no other fish in the aquarium -- ignoring rude behavior and 'bad looks' from competitors to get their share of the food. This enthusiasm tapers off until it almost appears like the fish are just 'gliding through the water' and picking up a bit of food, here and there. If it were a small child, we'd say they were, 'Playing with their food.' This is the end of the feeding time.

I would say the same is true of small children. If the reader is or has been a parent of a very young child, you get a sense of when the child has had enough to eat by their reaction to the food being offered. It is very similar to feeding fish. When their reaction to the feed is one of much less interest than at the start of the feeding process, the feeding time is over. At this point in time, food is not being eaten and drifts away from them and the hobbyist will need to chase it down and remove it. After a while though, the hobbyist will know this point and not add that last bit that will 'get away' from the fish.